Héctor Socas Navarro

Dates of the visit: 25/06/2014 to 30/07/2014.
Research line: Solar Physics
Institution visited: High Altitude Observatory (Boulder, EEUU).

Dr. Socas is collaborating with Dr. Rebecca Centeno, and Dr. Alfred de Wijn on the study of the long-term evolution of solar active regions as seen by Helioseismic and Magnetic Imager at SDO. Dr. Socas gave a seminar at HAO entitled NICOLE: An Open-Source, massively parallel code for non-LTE synthesis and inversion of spectral lines and Zeeman-induced Stokes profiles.

Currently Dr. Socas is a staff researcher at the IAC.

His main research interests are the solar oxygen abundance and the long-term evolution of solar active regions. At present he is also exploring the possible synergies between the DKIST and EST instrumentation.

The specific objectives of the visit to the HAO are:

1) Analyze Hinode observations and explore the optimal strategy for the determination of the O abundance using the forbidden 6300~A line.

2) Construct a few sequences of time-dependent observations of active regions on a local solar reference frame, corrected of perspective and with the magnetic field vector deprojected and disambiguated.

3) Look for possible indications of torsional oscillations in the magnetic field.

During this visit, important advances were made in two different research lines. In the project on sunspot torsional oscillations, we were able to complete the analysis of a full time-series sequence of an active region passage through the solar disk. The main conclusion of this analysis is that no such oscillations are observed, at least in the sunspot considered. In the second project, on the solar oxygen abundance, we completed the analysis of spectro-polarimetric data from the Hinode satellite. In these observations we have detected, for the first time, linear polarization signals in the forbidden OI line at 6300.3 A. There are currently two papers in preparation with these results.